Well packer



F. H. LEE

WELL PACKER June 15, 1954 3 Sheets-Sheet 1 Filed June 28, 1948 IN VEN TOR.

F. H. LEE

WELL PACKER' June 15, 1954 3 Sheets-Sheet 2 I Filed June 28, 1948 7m Amy/gave 4 I N V EN 10R; I ,Rwuas 5 21441 70 LEE,

BY WM 7.4m

F. H. LEE

WELL PACKER June 15, 1954 3 Sheet-Sheet s Filed June 28, 1948 M Z M ML m WM m N 1m M Patented June 15, 1954 UNITED STATES ATENT OFFICE WELL PACKER Application J une 28, 1948, Serial No. 35,554

23 Claims.

The present invention pertains to well packers, and particularly to packers that are useful in the cementing, bridging, acidizing, testing and producing of oil and gas wells.

Some well packers have normally retracted packings that are expanded against well casings, liners, or similar conduit strings, by compressing, or ioreshortening, the packings in a longitudinal direction and deforming them laterally outward. The force necessary to effect compression of the packing to the extent sufficient to insure its leak-proof seal against the conduit wall is sometimes relatively great. In fact, it may be greater than the actual force that can be imposed safely on the subsurface well equipment embodying the packing, or which is available within the design limitations of the equipment.

Accordingly, an object of the invention is generally to improve well packers, in order to ensure proper sealing of their packing members against the wall of the Well conduit.

Another object of the invention is to ensure leak-proof sealing of a well packer packing against a conduit wall with a lesser total compressive force imposed on the packing.

Still another object of the invention is to increase the unit pressure to which a packing structure is subjected in expanding it against the casing, for the same total force imposed upon the structure.

A further object of the invention is to provide a well packer capable of being anchored in a well conduit against movement or leakage under relatively high pressure and high temperature well conditions.

Another object of the invention is to provide a well conduit and cooperable packer apparatus, in which the packer can be anchored to the well conduit in a positive manner against movement in both longitudinal directions.

Still a further object of the invention is to provide an improved arrangement for anchoring a subsurface well tool in a well conduit.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of several forms in which it may be embodied. Such forms are shown in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

Figure 1 is a longitudinal View, partly in elevation and partly in section, of a well packer disposed within a well casing, with its parts arranged for running the packer through the cas- Fig. 2 is partial longitudinal section, disclosing the releasing of the looking elements which prevent upward movement of the packer in the casing;

Fig. 3 is a view similar to Fig. 2 of the locking elements fully anchored against the well casing;

Fig. 4 is a partial longitudinal section through the packer, illustrating its packing almost fully expanded against the casing;

Fig. 5 is a view similar to Fig. 4, disclosing the lower slips, or gripping members, in position for gripping the casing and preventing downward movement of the well packer therein;

Fig. 6 is a view similar to Fig. 5, disclosing the lower slips more firmly anchored against thecasing;

Fig. '7 is a view similar to Fig. 5, illustrating the packer fully anchored in packed-01f condition against the well casing;

Fig. 8 is a cross-section taken along the line 8-8 on Fig. 1;

Fig. 9 is a longitudinal section through a modifled form of the invention;

Figs. 10 and 11 are partial longitudinal sections disclosing the apparatus of Fig. 9 packedoff to different extents; and

Fig. 12 is a cross-section taken along the line I2--l2 on Fig. 9.

The well packer A disclosed in the drawings is run in a string of easing B, or similar well conduit, on the lower end of a tubular string C, or other running-in string, extending to the top of the well bore. The packer is adapted to be anchored in packed-off condition within and against a predetermined portion of the casing string in such manner as to be immovable in both longitudinal directions, and also to prevent leakage between the packer and well casing in both longitudinal directions.

The well packer A includes a generally tubular body 10 adapted to be anchored to the well casing B through the agency of upper and lower locking devices. Upward movement is to be prevented by a plurality of segmental lock elements I l disposed around the body and having inner tapered surfaces !2 engageable with a companion tapered surface I3 on an expander M initially secured to the body by one or more shear screws l5. The segmental lock members H are held initially in retracted position by one or more shear screws 3 l5 threaded into the expander M. The tapered surfaces l2, l3 on the lock members and exlpander converge in an upward direction, in order that upward movement of the expander I l within the lock members i I will urge the latter radially outward against the casing B.

Downward movement of the well packer is prevented by lower segmental slips ll, initially held in retracted position by shear screws l3 threaded into a lower expander l9 encompassing the body ill. The slips I1 and expander it have cooperable tapered surfaces 28, 2! converging in a downward direction, in order that upward movement of the slips ll along the expander 19 will move the former outwardly against the casing. The slips may have downwardly facing wickers or teeth 22 for engagement with the casing, to prevent their downward movement after having been moved outwardly.

The lower slips rest originally upon an abutment device, including a sleeve .23 secured to the body ill by one or more shear screws 25. This sleeve is movable relatively downwardly within an upwardly extending sleeve or skirt 25 of a guide 26 threaded onto the lower end of the body and forming part of the latter. During upward movement of the sleeve or skirt 25 with the body, fluid within the skirt 25 may escape through suitable bleeder holes 2'1.

ihe abutment device also includes a plate 28 engaging the undersides of the slips il; this engagement being maintained by a plurality of springs 29 surrounding pins or guides 39 slidable in bores 3! in the sleeve 23 and engaging the plate 23. When the shear screws l8 holding the slips i? to the lower expander iii are disrupted, the springs 29 will shift the slips upwardly along the expander and radially outward against the casing.

For the purpose of bridging the annulus between the tubular body Ill and well casing B, a packing structure is disposed on the body between the upper and lower expanders it, it. This structure may include a rubber packing sleeve 32, whose upper end is reduced in diameter to fit within a pocket 33 formed by and between the upper expander Hi and body Hi. The clearance space between the expander i l and body H3 is adapted to be bridged by a lead ring M, or other ring of pliant, inelastic material. In addition, a lead sealing ring 35 is disposed around the upper end of the rubber packing sleeve 32 adjacent the upper expander [4. This sealing ring 35 is designed to bridge the space between the expander and casing wall and prevent flow of the rubber packing material therethrough.

The lower end of the rubber packing member 32 is also reduced in diameter for the purpose of fitting within a recess 36 formed between a lead sealing member 3'! and the body ill. This lead sealing member has a depending skirt 3?! extending within an abutment or cylinder sleeve 39 engaging the upper head end 43 of the lead seal. This cylinder 39 extends downwardly along the packer body, with its lower head ll slidable along the body and engaging the upper end of the lower expander Hi.

In the annular cylinder space formed within the abutment cylinder 39 and the packer body ill, a device is disposed for enabling a greater unit pressure to be imposed upon the packing structure for a given total pull, or force, imposed upon the packer body. This device consists of a split, or segmental, piston t2 disposed within the cylinder 39 and having an inwardly directing medial flange i3 receivable within a companion peripheral groove or recess 44 on the packer body. Initially, shear screws :35 secure the split piston 42 to the packer body iil, with its flange substantially abutting a body shoulder 46, defining the upper end of the groove 44. When in this position, the lower end of the flange 33 is spaced above a body shoulder 4i defining the lower end of the groove 44.

The cylinder 39 and split piston 12 are also secured together initially by one or more shear screws 48, in order that they will, at first, operate as a single unit in expanding the packing structure against the casing wall.

The packer is designed to be anchored in the well casing simply as a result of moving the running-in string C longitudinally, as in an upward direction. The expansion of the upper lock members 1! against the casing B results from the engagement of a plurality of latches 49, or dogs, with a downwardly directed shoulder 50 defining the upper end of a locating groove 5i formed in a collar or coupling 52 threadedly secured to upper and lower casing sections 53, E i in order to hold them in spaced relation. These dogs are each disposed within a longitudinal slot 55 in a sleeve 56 surrounding the body l9, and resting upon the upper ends of the segmental lock members ii. The dogs are pivotally mounted on pins 57 secured to the sleeve 56, and are urged outwardly of the sleeve by springs 58 coiled around the pins, with one arm 59 bearing against the body it! and another arm 50 bearing against the dogs 49, to shift them outwardly.

The collar portion 52 of the casing string also has an internal locking groove ill for receiving the upper segmental lock members II, and lower wickers or teeth 62 adapted to be engaged by the lower slips H.

The well packer A is attached to the runningin string C and is lowered through a well casing B containing the grooved collar 52, until the packer is disposed below the collar. During this lowering movement the dogs 69 ride freely over the casing coupling spaces without interfering with the descent of the packer. The outer faces 63 of the dogs are longer than the longitudinal distance across the coupling spaces, so that the dogs will not engage in such spaces, even upon upward movement of the well packer in the easing string,

As stated above, the well packer is lowered to a point below the collar 52, after which the tubular string C is elevated slowly until the dogs 4? are disposed opposite the locating groove 5!. This groove is longer than the outer faces 63 of the dogs, to enable the springs 58 to urge them in an outward direction. Upon being disposed in the locating groove, further upward movement of the tubing string C and packer A is resisted by engagement of the upper ends of the dogs 19 with the locating groove shoulder 5t.

Upon such engagement of the dogs in the groove 5|, further upward movement of the sleeve 58 is prevented, which also resists further upward movement of the upper segmental lock members I I.

will now shear the screws 16 securing the lock members H to the upward expander I l. these screws have a lesser combined shear value than any other set of screws in the apparatus, their disruption enables the packer body it and upper expander l4, and also all of the packer The taking of an upward strain on the running-in string C and packer body ill Since.

elements therebelow, to move upwardly as a unit, shifting the expander l4 within the lock members H and urging the latter radially outward into the lock groove 6 i.

In order to facilitate locating of the lock members H in their companion groove 6!, the latter is made longer than the length of the members. These members H will be disposed substantially midway of the groove 6i when the locating dogs 49 are engaged with their companion shoulder 50 in the collar. This arrangement is illustrated in Fig. 2, from which it is apparent that there is a slight clearance space f4 between the upper ends of the lock members I! and the upper end 65 of the lock groove, which would allow the packer to move upwardly to a slight extent after having been set fully in the casing. To prevent this movement, the pivotal mounting 51 for the locating dogs are shear pins, with the lower ends 48a of the dogs initially spaced above the lower ends of the slots 55 in the sleeve 58.

After the lock members II have been disposed within the lock groove 6!, the taking of a greater upward strain on the running-in string and packer body It will cause the upper expander l4 and lock members H to slide upwardly as a unit and force the sleeve 56 in an upward direction. Since the dogs 49 cannot move upwardly, by virtue of their engagement with the shoulder 50, this upward force and movement will shear the pivot pins 5'1 and will allow the locking dogs H to move upwardly to the extent determined by their engagement with the upper beveled shoulder 65 of the look groove 6| (see Fig. 3). This shoulder is beveled to prevent the upper ends of the dogs 49 from being stopped in the lock groove while the well packer is being pulled upwardly through the collar 52. The upper outer ends of the lock members H may have a corresponding bevel to ensure surface contact between these members and the beveled shoulder 65.

The pivot shear screws 51 for the dogs 49 have a lesser shear value than the shear screws holding the upper expander M to the body l0. After the upper lock members II have been engaged with the groove shoulder 35, a further increase in the upward strain on the running-in string C and body ill will shear the screws [5 holding the upper expander to the body. The screws 45, 48 holding the split piston 42 to the body Ill and the cylinder 39 to the split piston have a greater shear value than the expander screws l5, so that upward movement of the packer body It will carry the piston 42 and cylinder 39 with it as a unit toward the upper expander i4. This latter member cannot move upwardly in view of its wedging relation with the lock members i I disposed within the lock groove 3|. The movement of the cylinder 39 and piston 42 toward the expander l4, which functions as an abutment, foreshortens the packing structure 32, 35, 31 and com-presses it outwardly against the wall of the casing (see Fig. 4).

The shearscrews 45 holding the piston 42 to the body ill have a much lesser shear value than the screws 48 holding the cylinder 39 to the piston. After the packing 32 has been expanded against the casing by a predetermined force, the shear screws 45 holding the piston 42 to the body are disrupted, allowing the body It to move upwardly within the piston to a limited extent, as determined by engagement of the lower shoulder 41 on the body with the piston flange 43. This upward movement of the body carries the sleeve 23 upwardly, shearing the screws I8 holding the slips I! to the lower expander l9 and expanding-the slips outwardly against the collar portion of the casing (see Fig. 5). If the collar is provided with the upwardly facing wickers or teeth 62, the companion teeth 22 on the slips will engage them and positively lock the lower expander l9 against downward movement within the well casing.

The foregoing shearing of the slip screws I8 will take place after the piston body screws 45 have been sheared, because the abutment sleeve screws 24 have a much greater shear value than the piston body screws. Of course, the body ID will only move upwardly within the piston 42 until the shoulder 47 and flange 43 engage, but this distance is sufficient to shear the slip screws l8 and move the slips at least partially toward the casing wall. If the slips must then partake of any further movement in order to engage the casing, such movement is supplied by the operation of the compressing springs 23, acting through. the guide pin 30 and the plate 28 engaging the.

lower ends of the slips (Fig. 5).

Intensification of the upward strain on the running-in string C and the body If) will first .move the abutment device 23, 28 firmly against the lower slips I1 and force them out against the casing, unless the groove shoulder 41 engages the piston flange 43 before this occurs. Whether or not the engagement of the abutment device with the slips first takes place will depend upon the inside diameter of the collar. If it does occur first, then the abutment shear screws 24 are disrupted, upon the taking of an upward strain on the body, to allow continued upward movement of the body without substantial restraint from the abutment 23 and the lower slip I1 (Fig. 6).

When the lower body shoulder 41 engages the piston flange 43, the strain on the running-in string and body can be further intensified to shear the screws 48 attaching the cylinder 39 to the piston 42. The continuation of the upward strain on the body I0 then moves the piston 42 upwardly within the cylinder 39 and forces the packing material outwardly against the casing to a greater extent (Fig. 7).

The packer is now anchored in packed-off condition against movement in both longitudinal directions. Upward movement of the body [0 is prevented and upward forces are transmitted to the casing through the flange 43, piston 42, pack-,

ing structure 31, 32, 35, upper expander l4 and upper look members ll. Downward movement of the tubular body I!) is transmitted to the casing through a split contractile lock ring 6! disposed within a groove 63 within the expander I9. This ring has upwardly facing teeth 69 engaging companion downwardly facing teeth 10 on the periphery of the body Ii From the lower ring 61, the downward force is transmitted through the lower expander l9 and slips I! to the casing teeth 32 or casing B.

It is apparent that the snug engagement between the upper segments H and lower groove shoulder 65 prevents any upward movement of the well packer within the casing. Similarly,

the engagement of the lower slips H with the.

casing prevents downward movement of the packer within the casing. The packing structure 31, 32, 35 prevents leakage between the body l0 and the casing B in both longitudinal directions.

By virtue of the arrangement disclosed for expanding the packing structure against the casing, a much greater expansive force can be imparted to this structure, ensuring its complete sealing with the wall of the Well casing. Prior to disassume ruption of the shear screws 48 holding the cylin der 39 to the piston 42, the latter two members move as a unit and transmit the total force or pull on the body [9 to the packing 32 across the annular area B existing between the exterior of the body ill and the exterior of the cylinder 39 (see Fig. 6, for example). The force that can be imposed safely upon the running-in string C and the body id can be transmitted through the joined cylinder 39 and the piston 42 to eiiect substantially full expansion of the packing structure against the casing.

However, still greater expansion is sometimes necessary to prevent leakage, particularly under high pressure well conditions. Accordingly, following disruption of the screws 48 securing the cylinder .59 to the piston 42, the cylinder is no longer movable in exerting pressure on the packing material. instead, the piston d2 then becomes the sole instrumentality for exerting a force upon the packing. Since the annular piston area P (see Fig. 7) is much less than the total annular area It across the piston 42 and cylinder 39, together, the imposition of the same total upward force on the running-in string C and body It will cause the piston 42 to apply a greater unit force or pressure to the packing material 31, 32, 35, ensuring its further outward expansion against the casing.

From the foregoing it is apparent that a booster mechanism has, in effect, been provided for intensiiying the force applied to the packing material. As an example, a total upward pull of fifteen thousand pounds on the body it transmitted through the piston 42 alone will subject the packing material to more than double the unit pressure than the same fifteen thousand pounds imposed upon the cylinder 39 and piston 42 acting jointly. A far greater packing-off eiiect is achieved without increasing the strain on the equipment beyond the desired amount.

A modified form of the pack-off intensifier portion of the invention is illustrated in Figs. 9 to 11. In this form, the packer body liia can be lowered in a well casing B on a tubular string C to a position at which a packing member 32a, in the form of a rubber sleeve, is to be sealed against the casing. This packing member is disposed around the body with its lower end engaging an abut- Inent 26a threaded on and constituting part of the lower end of the body. This abutment has a valve seat 'ltl'adapted to receive a suitable valve element 16 for closing a central passage 1? through the body against movement of fluid in a downward direction.

The upper end of the packing sleeve 32a is engageable by an actuating member, consisting of inner and outer sleeves i8, '59 secured together initially by one or more shear screws 89. The inner sleeve it! has a cylinder head 83 disposed immediately below the body head 82, and also has a skirt 83 extending upwardly from its head and disposed along the body head. Fluid is adapted to enter the cylinder space 84 between the cylinder and body through body ports 85. Leakage of fluid from this space in a downward direction is prevented by a suitable side seal it engaging the periphery of the body and disposed in a ring groove 3! in the head 8i. Leakage of fluid in an upward direction from the cylinder space 84 is prevented by a suitable side seal 83 engaging the skirt 83 and disposed within a peripheral groove, 89 in the'body head 32.

The well packer is run in the well casing'B on the tubular string C to the desired packing-off point, with the packin sleeve 32a in retracted.

ping member, such as a ball 15, is dropped or' pumped down the tubing string C and into engagement with the valve seat "15. Such engagement closes the body passage Ti and allows fluid under pressure to flow through the ports into the cylinder space 84. When sufiicient pressure has been imposed upon the fluid, the cylinder skirt screws are sheared, which moves the cylinder 83, 8!, and the interconnected sleeves l8, l9 downwardly toward the lower abutment 26a, compressing the rubber packing sleeve 32a, longitudinally and expanding it radially outward against the wall of the casing B (Fig. 10)

The fluid pressure may be increased to more firmly expand the packing 3201, against the casing, until the shear value of the screws 88 interconnecting the sleeves is exceeded and these screws disrupted. When this occurs, the fluid pressure acting over the annular cylinder area S then acts upon the packing 32a over the annular area T of the inner sleeve 18 only. The outer sleeve 19 is prevented from returning toward its initial position, by the expansive force of the rubber packing 32a, by a one-way clutch or brake device. This device may be in the form of rolling elements or balls EH located in tapered grooves 92 formed in projections :23 extending inwardly from the outer sleeve '19 through longitudinal slots 34 in the inner sl eve 78. It is apparent that the oneway characteristics of the clutch permit the outer sleeve 79 to move downwardly with the inner sleeve l8 along the body iila, but any tendency for the outer sleeve 79 to move upwardly along the body is pr vented by wedging of the ball elements 9! between the tapered surfaces of the sleeve groove 62 and the periphery of the body Ida.

As in the other form of the invention, most of the packing-oif of the packing 32a against the casing is accomplished by the two sleeves l8, 79 moving toward the abutment 29a, and compressing the packing 32a therebetween. When a predetermined force has been reached, in this instance in the form of fluid pressure acting on the cylinder head 81, the screws 88 are sheared and a given unit pressure acting on the cylinder head 8! then exerts its force on the packing 32a over a much smaller area, which causes the inner sleeve It to move downwardly within the outer sleeve 79 and apply a further compressive force to the packing (Fig. 11). Thus, the imposition of only the maximum pressure necessary to shear the screws 80 will result in a much greater unit compressive force on the packing sleeve 32a, ensuring its tight sealing engagement with both the packer body Ida and casing wall, thereby preventing leakage, even under comparatively high pressure and temperature operating conditions.

When the fluid pressure in the cylinder space 86 is bled off, the inner sleeve i8 is prevented from moving upwardly by a one-way clutch in the form of ball elements 95 in tapered grooves 96, in the sleeve 18 engageable with the periphery of the body Illa. This clutch permits downward movement of the sleeve 18 without restraint, but prevents its upward movement along the body.

The inventor claims:

1. In a well packer: a body; packing means on said body; means for expanding said packing means laterally outward including a plurality of members engageable with said packing means, means releasably coupling said members together, and means for initially moving said members together to expand said packing means by a com pressive force on said packing means applied over a particular area of said packing means and for then moving only one or" said members, after release of said coupling means, to further expand said packing means by a compressive force on said packing means applied over a smaller area of said packing means than said particular area.

2. In a well packer: a body; packing means on said body; means for expanding said packing means laterally outward including a plurality of members engageable with said packing means, means releasably coupling said members together, and means for applying a motive force to one of said members and through said coupling means to another of said members to first move said members together to expand said packing means by a compressive force on said packing means applied over a particular area of said packing means and for then moving only one of said members, after release of said coupling means, to further expand said packing means by a compressive force on said packing means applied over a smaller area of said packing means than said particular area.

3. In a well packer: a body; packing means on said body; means for expanding said packing means laterally outward including a plurality of members engageable with said packing means, frangible means coupling said members together, and means for initially moving said members together to expand said packing means by a compressive force on said packing means applied over a particular area of said packing means and for then moving only one of said members, after disruption of said frangible means, to further expand said packing means by a compressive force on said packing means applied over a smaller area of said packing means than said particular area.

4. In a well packer: a body; an abutment disposed on said body; packing means on said body engageable with said abutment; a plurality of members engageable with said packing means; means releasably coupling said members together; and means for initially moving said members together toward said abutment to expand said packing means by a compressive force on said packing means applied over a particular area of said packing means and for then moving only one of said members toward said abutone of said members and through said coupling means to another of said members to first move said members together toward said abutment to compress said packing means between said members and abutment by a compressive force on said packing means applied by both of said members over a particular area of said packing means and for then moving only one of said members toward frangible means releasably coupling said members together; and means for applying a motive force to one of said members and through said frangible means to another of said members to first move said members together toward said abutment to compress said packing means between said members and abutment by a compressive force on said packing means applied by both members over a particular area of said packing means and for then moving only one of said members toward said abutment, after disruption of said frangible means, to further expand said packing means by a compressive force on said packing means applied by said one of said members over a smaller area of said packing means.

'7. In a well packer: a body; an abutment disposed on said body; packing means on said body engageable with said abutment; inner and outer annular members engageable with said packing means; means releasably coupling said members for movement together; and means for applying a motive force to said inner member to move both of said members toward said abutment and effect expansion of said packing means; said coupling being releasable after joint movement of said members toward said abutment to then move said inner member only toward said abutment to effect further expansion of said packing means.

8. In a well packer: abody; an abutment disposed on said body; packing means on said body engageable with said abutment; inner and outer annular members engageable with said packing means, frangible means releasably coupling said members for movement together; and means for applying a motive force to said inner member to move both of said members toward said abutment and effect expansion of said packing means; said frangible means being releasable after joint movement of said members toward said abutment to then move said inner member only toward said abutment to effect further expansion of said packing means.

9. In a well packer: a body; an abutment disposed on said body; packing means on said body engageable with said abutment; inner and outer annular members engageable with said packing means; means releasably coupling said members for movement together; means for applying a motive force to said inner member to move both of said members toward said abutment and effect expansion of said packing means and to then move said inner member only toward said abutment, after release of said coupling means, to effect further expansion of said packing means; and means for preventing movement of said members in a direction away from said abutment.

10. In a well packer to be set in a well conduit: a body having a cylindrical periphery; initially retracted packing means on said cylindrical periphery of said body; means for imposing an axially directed force on said packing means over a particular area to compress and foreshorten said packing means to expand said packing means outwardly against the well conduit and also against said cylindrical periphery and for then effecting a decrease inthe area over which said compression and axially directed force is applied while said packing means engages said cylindrical periphery.

11. In apparatus of the character described: a well conduit having a lock groove and a locating groove therein; a well tool body; initially retracted means on said body shiftable outwardly into said lock groove; and means on said body engageable with said conduit within said locating groove for shifting said initially retracted means into said lock groove.

12. In apparatus of the character described: a well conduit having a groove therein; a well tool body; initially retracted means on said body shiftable outwardly against said conduit; and means on said body engageable with said conduit within said groove for engaging and shifting said initially retracted means outwardly against said conduit.

13. In apparatus of the character described: a Well conduit having a locating groove and a look groove therein; a well tool body; an expander on said body; initially retracted segmental lock members on said expander shiftable along said expander; a sleeve slidable on said body; and locating elements on said sleeve engageable with said conduit within said locating groove for e1"- fecting relative shifting of said sleeve along said expander and against said lock members to expan-:1 the lock members into said lock groove.

14. In a well packer: a body; abutment means on said body; a packing on said body engageable with said abutment means; gripping elements engageable with a well conduit and operatively associated with said abutment means for preventing movement of said abutment means; a plurality of members disposed around said body and engageable with said packing; means releasably coupling said members together; and means for initially shifting said members together toward said abutment means to expand said packing by a compressive force on said packing applied over a particular area of said packing and for then moving only one of said members toward said abutment means, after release of said coupling means, to further expand said packing by a compressive force on said packing applied over a smaller area of said packing.

15. In a well packer: a body; abutment means 5 on said body; a packing on said body engageable with said abutment means; gripping elements engageable with a well conduit and operatively associated with said abutment means for preventing movement of said abutment means; a plurality of members disposed around said body and engageable with said packing means; means releasably coupling said members together; and means on said body engageable with one of said members for shifting all of said members together toward said abutment means to expand said packing by a compressive force on said packing applied over a particular area of said packing and for then moving only said one of said members toward said abutment means, after release of said coupling means, to further expand said packing by a compressive force on said packing applied over a smaller area of said packing.

16. In a well packer: a body; means on said body for anchoring said body to a well conduit against upward movement; means on said body for anchoring said body to said conduit against downward movement; an initially retracted packing on said body between both of said anchoring means; inner and outer members on said body disposed one within the other between one of said anchoring means and one end of said packing; means releasably coupling said members for movement together; and means for imposing a motive force on one of said members to shift both of said members toward the other of said anchoring means to expand said packing by a compressive force on said packing applied over a particular area of said packing and for then moving only said one of said members toward said other of said anchoring means, after release of said coupling means, to further expand said packing by a compressive force on said packing applied over a smaller area of said packing.

17. In a well packer: a body; upper and lower expanders on said body; upper and lower anchoring members cooperable with said expanders to anchor said body to a well conduit against movement in both longitudinal directions; a packing on said body between said expanders; inner and outer annular members between one of said expanders and one end of said packing; frangible means securing said members together; and means on said body for engaging and imparting a motive force to said inner member to shift both of said members toward the other of said expanders and compress said packing therebetween.

18. In a well packer: a body; upper and lower expanders on said body; upper and lower anchoring members cooperable with said eXpanders to anchor said body to a well conduit against movement in both longitudinal directions; a packing on said body between said expanders; inner and outer annular members between said lower eX- pander and the lower end of said packing; frangi ble means securing said members together; and means on said body engageable with said inner member to shift both of said members toward said upper expander to compress said packing therebetween.

19. In a well packer to be set in a well conduit: a body having a cylindrical periphery; initially retracted packing means on the cylindrical periphery of said body when said packing means is in retracted position; means on said body for applying a compressive force to said packing means over a particular area of said packing means to expand said packing means outwardly against the well conduit and also against said cylindrical periphery and for then applying a compressive force to said packing means over only a portion of said area while said packing means engages said cylindrical periphery of said body. I

20. In a well packer: a body; an abutment disposed on said body; packing means on said body having an end portion engageable with said abutment; a plurality of members engageable with the opposite end portion of said packing means; means releasably coupling said members together; and means for initially moving said members together toward said abutment to expand said packing means by a compressive force on said packing means applied over a particular area of said packing means and for then moving only one of said members, after release of said coupling means, to further expand said packing means by a compressive force on said packing means applied over a smaller area or said packing means.

21. In a well packer: a body; an abutment disposed on said body; packing means on said body engageable with said abutment; inner and outer annular members engageable with said packing means; means releasably coupling said members for movement together; and means for applying a motive force to one of said members to move both or" said members toward said abutment and effect expansion of said packing means; said coupling being releasable after joint movement of said members toward said abutment to then move said one of said members only toward said abutment to effect further expansion of said packing means.

22. In a Well packer: a body; an abutment disposed on said body; packing means on said body engageable with said abutment; inner and outer annular members engageable with said packing means; frangible means releasably coupling said members for movement together; and means for applying a motive force to one of said members to move both of said members toward said abutment and effect expansion of said packing means; after joint movement of said members toward said abutment to then move said one of said members only toward said abutment to effect further expansion of said packing means.

23. In a well packer: a body; an abutment disposed on said body; packing means on said body engageable with said abutment; inner and outer annular members engageable with said packing said coupling means being releasable v means; frangible means releasably coupling said members for movement together; means for applying a motive force to one of said members to move both of said members toward said abutment and efieot expansion of said packing means; said coupling means being releasable after joint movement of said members toward said abutment to then move said one of said members only toward said abutment to effect further expansion of said packing means; and means for preventing movement of said members in a direction away from said abutment.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,476,727 Quigg Dec. 11, 1923 1,974,172 Branch Sept. 18, 1934 2,076,301 Meyer Apr. 6, 1937 2,121,002 Baker June 21, 1938 2,121,050 Hagan et a1 June 21, 1938 2,173,903 Halliburton Sept. 26, 1939 2,177,601 Smith Oct. 24, 1939 2,178,844 Baker Nov. 7, 1939 2,191,750 Brown -1 Feb. 27, 1940 2,197,920 Brown Apr. 23, 1940 2,323,085 Davis June 29, 1943 2,373,005 Baker Apr. 3, 1945 

